1. Field of the Invention
This invention relates generally to polyoxyalkylene polyether amino alcohols containing a tertiary hydroxyl group, their preparation, and their use as chain extenders in the preparation of flexible polyurethane elastomers and flexible polyurethane foam. The amino alcohols of the present invention, which may also be characterized as alpha, tertiary hydroxypolyoxyalkylene polyether-omega-amines are prepared from a polyalkylene glycol containing a tertiary hydroxyl group and a secondary hydroxyl group which is alkoxylated with ethylene oxide, propylene oxide or butylene oxide or a mixture thereof to form a polyether intermediate which is then reductively aminated to provide the desired amino alcohol. The thus prepared materials are useful as chain extenders in the preparation of flexible polyurethanes, such as flexible polyurethane elastomers and flexible polyurethane foams, coatings, adhesives, sealants, etc.
2. Prior Art
Prescott et al. U.S. Pat. No. 3,179,606 is directed to cellular polyurethane foam made from a polyoxyalkylene polyether polyol and a polyethylene polyamine.
Edwards et al. U.S. Pat. No. 3,297,597 is directed to Mannich condensates of a phenol, formaldehyde and an alkanolamine and to their use in the manufacture of polyurethanes.
Lee et al. U.S. Pat. No. 3,236,895 discloses diamines prepared from polyoxypropylene glycol starting materials.
Yeakey U.S. Pat. No. 3,654,370 is directed to polyoxyalkylene polyamines prepared from the corresponding polyoxyalkylene polyols.
Moss et al. U.S. Pat. No. 3,838,076 is directed to polyurethane foams prepared from partially aminated polyoxyalkylene polyether polyols wherein the amine groups are introduced by reductive amination of the polyoxyalkylene resin in the presence of a hydrogenation-dehydrogenation catalyst, hydrogen and ammonia.
Cuscurida et al. U.S. Pat. No. 4,296,213 is directed to polyurea polymer polyols made by reacting a hydroxyl-containing amine, a polyether polyol and an organic polyisocyanate. The hydroxy-containing amine is an alkanolamine or a heterocyclic compound such as hydroxyethyl piperazine, etc. The use of 2-hydroxyethylethylenediamine is disclosed as a suitable hydroxyl-containing amine.
U.K. Patent Application No. 2,072,204A is directed to modified polyols prepared by polymerizing an amino alcohol such as an alkanolamine with a polyisocyanate in the presence of a polyether polyol. Amine starting materials that are mentioned include compounds such as the ethanolamines, methyl diethanolamine, the isopropanolamines, etc. It is stated that it is possible to use secondary or tertiary alkanol amines which are halogen substituted at the alkyl group.